If we get rid of something every time it gets hijacked by nutters and extremists, then we can say goodbye to the German National anthem, the Union Jack, the Premier League, God save the Queen, 10 green bottles (10 German bombers) and Hen Wlad Fy Nhadau (whales! whales! bloody great fish are whales..)
True to a point but the Union flag and God Save The Queen are have official and national status. Whilst they can be used by extremists in jingoistic actions they are equally used by people of all backgrounds, colours and creeds as part of an overall national identity. Black athletes, for example, are equally proud to wear the flag, sing the anthem and represent the UK in sports events as any white athlete. Although Britain has a colonial history and certainly cannot claim to be free of racism, the flag and anthem do not evoke such strong feelings when used in genuinely non-extremist situations and it is possible to delineate between the appropriate and inappropriate use of the the Union flag and the national anthem.
As far as I know, the Confederate flag has no nationally official status. I agree however, that it might be possible that the passing of time may have diminished it's intrinsic link with a war closely associated with slavery and may have more general, idealistic connotations - the question is has it or has it done so enough so that it can readily be accepted as representative of the ideals of the majority of the people who live in the Southern states?
It might be being used as a scapegoat for wider issues but if few black people can find any positive association with the Confederate flag then surely questions over it's use, especially in an official capacity.